Microphone windshield



March 14, 1933. K -r5 1,901,06P

MICROPHONE WINDSHIELD Filed March 27, 1931 2 Sheets-Sheet l WINDINVENTOR RALPH K. SPOTTS QATTORNEY 45 the microphone.

PatentedMar. 14, 1933 UNITED STATES PATENIO-JF'FICE RALPH x. srorrs, orLos menus, cam-roman, assrenon. 'ro RADIO-KEITH- onrnmm oonronuron, Acoaroaarron 03mm mcnoraonn wmnsmnnn Application filed larch 27, 1931.Serial Ho. 525,718.

The present invention relates to a system and apparatus for shielding amicrophone used for pick-up 'work in connection with sound recording ortransmission from wind 5 or pressure disturbances. In using a microphonein the open for any pick-up I purpose, and particularly when making arecord of sounds, it may be that the wind, or the motion of the microhone through the air in the case it is locate on a moving vehicle, willcause unpleasant sounds to be picked up and recorded. The strength ofthese sounds in fairly moderate winds ma exceed that of the sound it isdesired to pic up and record, which fact frequently precludes the makingof combined sound pictures under otherwise ideal conditions. Thisimposes a considerable additional limitation.

may be made. It is the object ofthe present invention to produce a newand improved method and apparatus for sound recording.

upon the time during which talking movies It is a further object of thisinvention to provide a means for recording sounds in a wind.

An additional object of this invention is to produce a device forshielding a microphone, adapted to be used in the open, from aircurrents.

It is also an object of this invention to provide an apparatus forproducing improved sound effects. I

These and other objects of my invention will become apparent from thefollowing specification taken in connection with the appended drawings.

In accomplishing the objects of my invention, I provide a wind-shieldaround the mi- 40 crophone used for pick-up purposes, as, for instance,in connection with sound recording apparatus as in talking motionpicture productions. The wind-shield is preferably of a streamline typewhich completely encloses The head of the windshield is of wind proofmaterial and the remainder of the wind-shield "is streamlined and ofsound transparent material. The design is carefully made to preventdifferences of pressure or eddy currents resulting inside ,material toprevent resonances which would produce undesired noises in the output ofthe microphone. The sound transparent material is stretched to avoidflapping.

Having thus briefly descrlbed my invention, attention is invited to theaccompanying figures in which;

Figs. 1 and 2 r present a side elevation and front view resp ctively,partially in cross section, illustrating the preferred form of myinvention; and,

Figs. 3 and 4 are top and side views respectively of an alternative formof windshield em odying the present invention.

Referring now more particularly to Fig. 1, the microphone 1, attached tothe usual microphone amplifier v3 and suspended by means of the hanger 5in the usual manner, is completely surrounded .b a ze pelin shapedwind-shield generally indicate at 7. The wind-shield 7 consists of alight framework 8 suitably covered as will be explained hereinafter andis clamped to the barrel of the amplifier 3 by means of a clamping ring9, surrounding the barrel thereof, adapted to be secured by anyappropriate fastening. The microphone is completely enclosed, and theform thereof is as nearly a perfect streamline as it is possible toconstruct. The material of the covering is composed of two parts; 5 part11 covering the nose of the wind-shield being of wind proof materialwhich is sufficientlyrigid and dead as to avoid flapping. The materialof this portion of the windshield may be the same as that covering therest of the bodyas described hereinafter, but

with the flowof air need be only sufliciently impervious to preventeddies passing therethrough. The porous material does not permit thepassage of air as there is never sufficient pressure or vacuum creatednext to it to. force the air through it. China silk or fine muslin issufiicientl soundtransparent to ermit the making 0 a very*satisiactorypic -u by a microphone enclosed in the wind-sliield of my invention. Theinterior of the nose portion 11 is filled with a sound absorbentmaterial to prevent any possible resonance in this air tight portion.

It is obvious that the microphone windshield shown in Figs. '1 and 2must be at all times turned to oint into the wind and that it would beine ective to prevent undesired wind noises being picked up bymicrophone 1 unless it is so pointed. Therefore, this type ofwind-shield is not satisfactory for use in gusty or uneven winds,although when the wind is steady, or the pick-up apparatus is being usedon a moving vehicle, where the efiectof the motion of the vehiclegreatly exceeds that of the actual wind, this type of wind-shield ismost satisfactory.

However, under the condition of shifting winds, I find it desirable touse the modification shown more particularly in Figs. 3 and 4 to whichattention is now invited. In this modification, the wind-shieldgenerally indicated at 13 completely surrounds the microphone 1connected to the amplifier 3. A ring 13 similar to that of. Figs. 1 and2 serves to secure the windshield to the amplifier. The wind-shield isconstructed of framework 15 covered by the covering material. Thestreamline permitted by this form is necessarily not nearly as perfect,but the doped portion of the covering material is inthe form of a ringadapted to act as both the nose or pressure area, and the tail or vacuumarea depending up n of the wind. The windproog zone isindicated at 17.The bottom portion 19, through the direction microphone mounted withinsaid assembly with its sound wave receiving surface paralent portions, amicrophone arranged with in said wind-shield to receive the soundtransmitted through said transparent portion, and means whereby therelation between said microphone and said wind-shield may be adjusted.

3. A sound pick-up device including an amplifier, a streamlinedwind-shield assembly mounted upon said amplifier, and a microphonemounted within said wind-shield and connected to said amplifier. r

4. A sound pick-up device including an amplifier, a streamlinedwind-shield assembly adjustably mounted on said amplifier,

and a microphone mounted within said windshield and connected to saidamplifier.

- RALPH K. SPOTTS.

which the sound passes to the microphone,

is quite accurately streamlined. The interior of the ring portion may befilled with sound absorbent material to prevent resonances,

which filling, however, will not afiect the passage of sound through thesound transparent covering 19 to the microphone.

It is obvious that whereas. the nose portion 11 of the wind-shield ofFigs. 1 and 2 and the zone 17 of the mushroom type shown in Figs. 3 and4 are described as wind proof, these portions may be partially or:wholly sound opaque as desired.

Having thus described my invention, attention is invited to the factthat various modifications may be devised coming within its scope, and Iam therefore not to be limited to the specific embodiments shown anddescribed for the purpose of illustration only, but by the actual scopeof my invention as set forth and determined in the appended claims.

' I claim 1. A sound pick-up device including a streamlined wind-shieldassembly,v and a

